This LED ring light will fit on a microscope objective with 54mm outer diameter. It is held in place with a 3d printed nut that tightens the grip. It's made of three printed parts: reflector/ring, nut, cover/shade. You will also need 2 LED strips, one 250mm (5 50mm sections), and one 350mm (7 50mm sections). I added a new nut design: 'LED_RingLight-nut2', that has it's thread radius reduced by 0.1mm, to make it easier to turn. Your support kindly accepted here: https://paypal.me/ZigaM3. Or here, with LBRY (LBC) credits, through my Odysee channel: https://odysee.com/@ZigaMDIY:9